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Changes of the Vistula River channel pattern and overbank accumulation rate in the Carpathian Foreland (South Poland) under human impact

Łajczak Adam

Studia Geomorphologica Carpatho-Balcanica

2021

Vol. 55

153--184

The rate of overbank accumulation in the Vistula floodplain within the Carpathian Foreland has increased since at least the 16th century as a result of drainage basin deforestation (mainly in the Carpathian portion) and agricultural use of this area. However, since the 1850s, additional causes have included deepening of the Vistula channel and its tributaries (mainly the Carpathian ones) initiated by regulation works which delivered additional sediment for overbank accumulation within the inter-embankment zone. Since the 1950s, a rapid decrease in the overbank accumulation rate was noted. This resulted from the retention of the majority of the sediment by deep reservoirs on the Carpathian tributaries of the Vistula, reforestation of the Carpathian portion of the drainage basin, and the slowing down of the rate of deepening of the Vistula channel. An estimate was made of the differentiation of the rate of overbank accumulation within the inter-embankment zone in the longitudinal profile of the study section of the Vistula. The Author proposed a modified model of temporal change of the rate of overbank accumulation in section of the course of the Vistula studied, distinguishing a stage in which change was influenced by regulation works.

Rzeźba strukturalna obszaru Świętokrzyskiego Parku Narodowego

Łajczak Adam, Urban Jan, Rączkowska Zofia, Wałach Grzegorz

Przegląd Geologiczny

2020

vol. 68, nr 2

102--111

The area of the Świętokrzyski National Park is one of the most evident examples of structural morphology in Poland. Its relief is clearly determined by bedrock lithology: the hill ranges are composed of hard quartzitic sandstones of the upper Cambrian (Łysogóry Range) and the Lower Devonian (Klonowskie Range), while the depressions, usually vast and flat-bottomed, are distributed on outcrops of soft, easily weathered and eroded Ordovician and Silurian shales, greywackes and sandstones. The parallel pattern of hill ranges and depressions, as well as a mesh-grid pattern of river valley systems and the antecedent character of river gaps, reflects fold tectonics modified by transverse faults. Such a morphology developed during the Paleogene and Neogene under hot and then warm, gradually cooling climatic conditions. In the Pleistocene, principally under the periglacial conditions, block fields (symbols of the Świętokrzyski NP) and crags (crests, table-like forms, cupolas and spurs) were formed. The shape and spatial position of most crags are related to geological structures.